1. Field of the Invention
This invention relates to a pressure or temperature responsive device and, more specifically, to a novel pressure or temperature responsive switch system also having a defined temperature gradient between the pressure or temperature sensor and the electrical output leads.
2. Brief Description of the Prior Art
Pressure and temperature responsive switches generally are provided with a pressure or temperature responsive element which will open or close a switch when a predetermined minimum pressure or temperature is sensed by the responsive element. Examples of such temperature responsive switches are found are found in the patents of Boulanger (U.S. Pat. No. 4,641,121) for water proof construction and Boulanger (U.S. Pat. No. 4,349,806). Further examples are found in U.S. Pat. Nos. 4,296,287 and 4,638,721 for pressure switches.
A problem which often exists in the environment of such switches is that they are to be mounted on a high temperature device, such as high temperature piping. This high temperature often exceeds the temperature rating of some of the components of many such switches, such as, for example, standard wire insulation and polymeric seals. For this reason, many water proof pressure and temperature responsive switches of the prior art could not be operated on high temperature equipment or could be so used only with the use of relatively complex and expensive parts and materials. It is therefore apparent that a temperature or pressure responsive switch which can be used on such high temperature equipment in moderate temperature environments and which can be produced from relatively inexpensive parts and materials would provide a substantial advance in the art.